Erigeron tracyi |
Erigeron karvinskianus |
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running fleabane |
erigeron karvinskianus, Karwinsky's fleabane, Latin American fleabane, Mexican fleabane, Santa Barbara daisy, Spanish daisy |
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Habit | Annuals, biennials, or short-lived perennials, 2.5–8(–12, 18) cm; usually taprooted, sometimes fibrous-rooted, caudices simple or branched. | Perennials, often short-lived, 10–100 cm; fibrous- or taprooted, caudices woody, usually simple, stems sometimes rooting adventitiously. |
Stems | first erect (greenish proximally), then producing herbaceous, leafy, prostrate runners (stoloniform branches, sometimes with rooting plantlets at tips), densely hirsutulous (hairs spreading-deflexed, of relatively even lengths and orientations), sparsely minutely glandular. |
erect to sprawling or decumbent (small leaf tufts in axils of larger leaves), sparsely strigose to glabrate, eglandular. |
Leaves | mostly basal (persistent in early season); blades oblanceolate to spatulate (obovate-elliptic laminae), 10–30(–60) × 3–6(–12) mm, cauline abruptly reduced distally, margins entire, dentate, or lobed, faces densely hirsute, eglandular. |
basal (and proximal cauline withering by flowering) and cauline; cauline blades elliptic to obovate, mostly 10–40(–50) × 5–13 mm, usually relatively even-sized along stems, margins entire or with 1–2 distal pairs of acute, mucronulate teeth or lobes, faces sparsely and loosely strigose to hirsuto-villous, eglandular. |
Involucres | 3.5–4.5(–6) × 6–9(–12) mm. |
2.5–3.5 × 7–10 mm. |
Ray florets | 60–130; corollas white, often purplish abaxially, sometimes with an abaxial midstripe, 5–9 mm, laminae not coiling or reflexing. |
45–80; corollas 5–8 mm, laminae not or slightly coiling, white, sometimes drying pinkish. |
Disc corollas | 2–3 mm (throats indurate and slightly inflated). |
2–3.1 mm. |
Phyllaries | in 3–4 series, sparsely to moderately hirsute, minutely glandular. |
in 3–4 series, sparsely strigose to hirsuto-villous or glabrate, sometimes minutely glandular. |
Heads | 1(–3 rarely, from midstem or proximal branches). |
1–5 (usually from branches distal to midstem). |
Cypselae | 0.7–1.3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 12–16 bristles. |
1–1.4 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 15–27 bristles. |
2n | = 27. |
= 18, 27, 36 (from Mexico, Central America, South America). |
Erigeron tracyi |
Erigeron karvinskianus |
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Phenology | Flowering Mar–Oct. | Flowering Apr–Aug. |
Habitat | Desert scrub, grassy slopes, oak chaparral, pinyon-juniper woodlands, Douglas fir-ponderosa pine | Moist, disturbed sites, shaded rock walls, cement cracks |
Elevation | 700–2300(–2400) m (2300–7500(–7900) ft) | 300–1100 m (1000–3600 ft) |
Distribution |
AZ; CO; KS; NM; NV; OK; TX; UT; Mexico (Baja California, Chihuahua, Coahuila, Durango, Sonora, Zacatecas)
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CA; Mexico; Central America [Introduced in North America; introduced in West Indies, South America, Europe, Africa, Pacific Islands, Australia]
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Discussion | In March through June, plants of Erigeron tracyi produce leaves in a basal rosette usually with a single, erect, monocephalous, stem. Stoloniform branches are soon formed (often recognized on pressed specimens by the leaves mostly on one side of the branches), and by the end of the season (August through October), prostrate runners are usually evident, sometimes forming terminal, rooting plantlets. Erigeron tracyi is similar in habit to E. flagellaris, particularly in the herbaceous stolons or stoloniform branches; the stem pubescence of E. tracyi is different, the stolons much less commonly produce rooting plantlets at the tips, and the plants tend to be perennial with woody or lignescent caudices, although they are variable both in habit and duration. Apparent hybrids with E. modestus and E. flagellaris are occasionally encountered, and the most common form of E. tracyi is perhaps (speculative) a stabilized, apomictic hybrid between the latter and E. divergens. All chromosome counts thus far have shown E. tracyi to be triploid and asynaptic. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Erigeron karvinskianus is most abundant in tropical and subtropical regions; it is widely cultivated and escaped. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 340. | FNA vol. 20, p. 337. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. cinereus, E. colomexicanus, E. commixtus, E. divergens var. cinereus | E. mucronatus |
Name authority | Greene: Pittonia 5: 59. (1902) | de Candolle: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 285. (1836) |
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